Grace Mick, 36, was last spoken to around 12.50am on Tuesday, 7 January and is six months pregnant.
She is of slim build, around 5ft tall and has shoulder length dark hair.
Grace usually wears pink and black trainers, possibly Sketchers, with a black padded jacket.
She is known to have links to Old Street, Islington and Edmonton.
Officers are very concerned about her welfare and are asking her to make contact.
Call the Missing Persons Unit at Central North via 101 if you have seen Grace, quoting Cad 6375/06Jan.